Dr. David Nabarro says he wants to rid the world of two diseases that are close to being eradicated: polio and guinea worm. Polio exists mainly on the Pakistani-Afghan border and in northern Nigeria. Both are conflict zones, where vaccine workers risk their lives to immunize children.

“The last part of eradicating any disease is always the hardest part,” Nabarro said during a visit to VOA. “If you don’t do it, you lose everything. To do it, you’ve got to really bring all the energy and commitment you can to bear.”

The World Health Organization has worked to eliminate polio for more than 30 years. Nigeria was to be declared polio-free this year, meaning the country had no cases for three continuous years, but then the disease returned.

“We must remain vigilant and focused until we are certain that the last case has been found and that we have got everybody protected,” Nabarro said.

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Nabarro also wants to rid the world of Guinea worm, a disease that starts when people drink water containing fleas infected with guinea worm larvae. The larvae grow in human intestines. And while it is not life-threatening, it is painful when the worm emerges.

In 1986, about 3.5 million people had Guinea worm disease. Last year, 25 people had it. This was the result of efforts by United Nations agencies, the Carter Center, which was founded by former U.S. President Jimmy Carter, and the U.S. Centers for Disease Control and Prevention.

Nabarro wants to make more inroads in ending malaria, a disease that threatens nearly half the world’s population. Even through malaria can be prevented and cured, the WHO says it caused nearly half a million deaths in 2015.

Ebola epidemic

During the Ebola epidemic, Nabarro visited the West African countries ravaged by the disease as the U.N. special envoy on Ebola. It took the world a long time to put together an effective response to the epidemic, and before it was over more than 11,000 people died.

The WHO was heavily criticized for the way it handled the pandemic. Nabarro wants to make sure a tragedy of this magnitude does not happen again because of a lack of preparedness.

“I want to be sure the world as a whole helps nations to respond quickly when there’s a threat of infection. Usually, that means that the problem doesn’t get out of control,” he told VOA.

Life of public health service

Nabarro has spent his life working in public health. He worked in Iraq with Save the Children in 1974. He continued to work in public health positions until he joined the World Health Organization in 1999 and has worked at the WHO and for the U.N. since then. Nabarro has worked on malaria programs.